The Precision Radiation Instruments Model 108, also known as the “Snooper,” was an inexpensive Geiger Mueller survey instrument primarily designed for  prospecting. According to the manufacturer, it was the instrument of choice "if you are an amateur, vacationer, or economy minded prospector."

   This particular unit was shipped by Montgomery Wards in Oakland CA from Alameda CA in the mid ’50s. It was apparently wrapped only in shipping tape. I have not tried to make it work but it is in very good condition. I am including the batteries it was found with for reference, they are in good condition, not leaking in any way and fit in the intended spots.

   The Snooper is turned on with the black plastic on/off switch and then the metal button just above the switch (pointing towards the lower right in the photo) is pushed two or three times. The instructions note that the button should not be pressed once the unit is working.

The detector output is monitored via headphones. The Snooper has no speaker, nor does it have any visual indication of the detector output, e.g., a flashing light or meter.

   Detector: Thin-wall GM tube inside upper portion of case.